Outdoor & Yard / Compounds / Sodium arsenate

Sodium arsenate in the yard and garden

Moderate risk for your yard

Safety profile for Sodium arsenate relevant to people, pets, and pollinators.

What is sodium arsenate?

The IUPAC name is Trisodium arsenate dodecahydrate.

Also known as: Trisodium arsenate dodecahydrate, Disodium arsenate, Sodium arsenate, dibasic, Sodium biarsenate.

IUPAC name
Trisodium arsenate dodecahydrate
CAS number
7778-43-0
Molecular formula
Na3AsO4•12H2O
Molecular weight
424.04 g/mol
SMILES
O[As](=O)([O-])[O-].[Na+].[Na+]
PubChem CID
24500

Risk for people, pets,

Moderate risk

Regulatory consensus

2 regulatory and scientific bodies have classified Sodium arsenate. The classifications differ — that's the data.

AgencyYearClassificationNotes
EPA——
IARC——

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where your yard encounter sodium arsenate

  • pesticide production
  • herbicide manufacturing
  • wood preservatives (historically)
  • laboratory reagent

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Sodium arsenate:

  • Monosodium phosphate
    Trade-offs: Lower biocidal efficacy. Phosphate runoff causes eutrophication.
    Relative cost: 0.5×
  • Copper-based wood preservatives (ACQ, CA-C)
    Trade-offs: More corrosive to fasteners. Requires stainless steel or hot-dip galvanized hardware.
    Relative cost: 1.3×

Frequently asked questions

What products contain sodium arsenate?

Sodium arsenate appears in: pesticide production; herbicide manufacturing; wood preservatives (historically).

See Sodium arsenate in the outdoor app

Look up products containing sodium arsenate, compare to alternatives, and explore the full data record.

Open in outdoor View raw API data

Sources (1)
  1. ATSDR Toxicological Profile — CAS 7778-43-0 — reference

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →